1. Field
One or more embodiments relate to an optical device, and more particularly, to a photographic lens optical system for cameras.
2. Description of the Related Art
Recently, the use and application of cameras including solid-state imaging devices such as complementary metal oxide semiconductor (CMOS) image sensors or charge coupled devices (CCDs) have greatly increased. Also, the degree of pixel integration in solid-state imaging devices has increased to improve the resolution of cameras. Along with this, small and lightweight cameras have been developed by improving the performance of lens optical systems included in the cameras.
In general, lens optical systems of small cameras are constituted by many lenses, for example, at least four lenses, so as to guarantee performance. For example, lens optical systems of high pixel count cameras generally include four or five lenses. If a lens optical system includes many lenses, the field of view (FOV) and aberration correcting ability of the lens optical system may be improved. However, it may be difficult to reduce the size and weight of the lens optical system and the size and weight of a camera using the lens optical system. In addition, lens optical systems of existing camera phones include at least one glass lens to improve performance. However, manufacturing costs of glass lenses are relatively high, and it is difficult to reduce the size of lens optical systems including glass lenses because of limitations in forming/processing glass lenses.
Therefore, there is a need for a small, wide-FOV lens optical system having improved properties such as a high aberration correcting ability and a high degree of resolution.